Power operated mechanism



Aug. 16, 1938. w. M. GILMAN ,1

- POWER OPERATIED MECHANISM 7 Filed Sept. 28. 1935 Patented Aug. 16, 1938 PATENT OFFICE POWER OPERATED MECHANISM V Wilbert M. 'Gilman, Cambridge, Mass. Application September 28, 1935, Serial No. 42,678

2 Claims.

This invention relates to mechanism for moving a member between two positions, such as a mechanism for moving a valve member in an automatic pressure operated valve. More particular-- ly, the invention is directed toumechanism of this general type in which the member to be moved is held in one of its positions while potential energy is developed which is released to snap the member to its other position.v

It is an object of the invention to provide an improved mechanism of this general type which is simple, efllcient, reliable and can be menufactured at low cost and possesses long life.

It is a further object of the invention to provide such a mechanism capable of a wide range of adjustment which can be conveniently effected to adapt it to special conditions of use. I

These and other objects of the invention will be more clearly understood from the following description in conjunction with the accompanying drawing, in which:

Figs. 1 and 2 are sectional elevational views oi a valve embodying the invention showing the parts in diiferent relative positions.

Before explaining in detail the present invention it is to be understood that the invention is not limited in its application to the details of construction andarrangement of parts illustrated in the accompanying drawing, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation, and his not intended to limit the invention claimed herein beyond the requirements of the prior art.

The invention is illustrated in the accompanying drawing as embodied in an automatic pressure operated valve comprising a cup-shaped casing ithaving inlet and outlet openings Hand 2 respectively. A sleeve I2 is mounted within the casing l and for this purpose is provided with an extension I4 threaded to engage a threaded re- 'cess l5 communicating with the outlet opening l2. The sleeve I3 is provided with a passage l5 adapted to receive and'slidably guide a valve member l1 adapted to engage a valve seat It formed in the upper end of a plug II which is threaded into the extension ll of the sleeve I2 and has a passage 25 providing communication between the passage l6 and the outlet opening l2. Passages 95 are formed in the-sleeve I! to provide communication between the inlet and outlet openings II and i2. A slide 25 is also movably guided in the passage l5 and epgtends upwardly into an enlarged passage 26 in the upper end of the sleeve it. The slide 25 may be provided with a key-way 8 adapted to be engaged by a key carried by the sleeve l3.

A sleeve 2! having an inwardly extending flange 5 28 at its lower end surrounds the slide 25 and is siidably guided in the passage 25. The upper end of the sleeve 21 is internally threaded to receive a plug 29 having an annular shoulder 30. A belt lows ii is secured at its lower end between the top of the casing l0 and a clamping ring 32 secured to the casing'by screws 23. The other end of the bellows ii is secured to the outer edge of an annular disc 34, the inner edge portion of which extends upwardly and inwardly and is secured between the shoulder upon the plug 29 and the top of the sleeve 21. A cover sleeve I5 surrounds the bellows II and is secured at its lower end by screws. 15 to the casing Ill. The top of the sleeve i5 carries a strap 'll having a threaded opening to 20 receive a. plug ll. A spring 80 is interposed between the disc 34 and an adjusting nut 8| carried by the threaded inner end 01' the plug 18 and held in its adjusted position by a lock nut 82. An adjusting screw 52 is carried by the plug 18 and exbtends into a cavity 54 therein. A spring 85 extends between the top of the plug 29 and the lower end 01' the adjusting screw 53. The adjusting screw 52 is held in its adjusted position by a lock nut 85'.

The reduced lower end 45a of the slide 25 extends into a cavity 41 in the valve member I! and carries a pin which projects laterally from the slide 25 into an enlarged opening 48 in the valve member i'l thereby providing a lost motion connection between the slide 25 and the valve member ii. A spring 50 is interposed between the lower end of the slide 25 and the bottom 01' a cavity 41 in the valve member I I. A spring surrounds the slide 25 and is interposed between 40 washers 4| and 42 adapted to engage respectively a shoulder formed upon-the slide 25 and the lower face of a nut 44 threaded upon the upper threaded end of the slide 25 and held in place by a ioclrnut 45, the plug 29 being provided with a 45 cavity 45 adapted to receive the nuts 44 and 45.

The slide 25 is provided with spaced shoulders 5| and 52 adapted to be engaged by the inner ends of bell crank levers or triggers 53 and 54 which extend through a slot 55 in the sleeve l3 and are pivotally mounted upon bearings 51. The levers 52 and 54 are connected by a spring 60. .Engagement oi the levers 52 and 54 with the shoulders 5i and 52 serve to prevent movement'oi the 55 slide II and hold the valve member il in its closed and open positions respectively.

The sleeve 21 and the plug 29 together serve as an actuator and are so arranged that the inwardly extending flange 28 and the bottom oi the plug may engage the washers 4| and 42 respectively. An arm H is secured by screws 82 to the sleeve 21- and is provided with shoulders 65 and 6 adapted to engage the outer ends of the levers it and I4 respectively to release the latter from their holding positions.

The outer surface of the sleeve I8 is spaced from the, inner wall of the casing Ill so as to provide a passage I for the movement of the arm I and the outer ends of the levers 53 and 54, this passage also serving to provide communication between the inlet openings ii and the interior of the bellows I i. In order to retard the flow oi fluid between the inlet openings ii and the bellows, a ring Ill may be positioned in the passage 88 with itsouter edge engaging a shoulder ll upon the inner wall of the casing and its inner edge engaging a shoulder 12 upon the outer suriace oi the sleeve II.

As the pressure of fluid entering the bellows 3| through the inlet openings ii and passage 80 increases the bellows Ii will expand causing the disc 34, the plug 29 and the sleeve 21 to rise. The upward movement of these parts is resisted by the springs 00 and 85. As the pressure of the fluid within the bellows .Ii decreases the springs II and I! tend to move the disc, plug 29 and sleeve 21 downward.

Assuming that the valve member I1 is in its closed position. as indicated in Fig. 1, and the pressure of the fluid within the bellows Si is increasing, the inwardly extending flange upon the sleeve 21 will engage the washer ll and will tend to move the slide 25 upward through the medium of the spring 40. However, since the valve II is in its closed position, engagement of the trigger I with the shoulder Ii prevents movement of the slide 25 upwardly. Consequently, the upward movement of the sleeve 21 will cause the spring 40 to be compressed and build up potential energy therein. As the upward movement of the sleeve 21 continues the shoulder '8 upon the arm I will engage the outer end of the trigger l3 and release the latter from engagement with the shoulder Ii at about the time the top of the disc 34 reaches the position indicated by the dot and dash line A, thereby permitting the potential energy stored in the spring 40 to act to move the slide 25 upwardly and, consequently, move the valve member H from its closed position as shown in Fig. 1 to its open position as shown in Fig. 2. As the slide 25 moves upwardly the spring will move the trigger 54 into engagement with the shoulder 82 thus preventing downward movement of the slide II and holding the valve member ll in its open position.

As the pressure of the fluid within the bellows ll decreases. the springs II and it will move the disc 84, plug 29 and sleeve 11 downwardly. In so doing, the bottom of the plug 2! will engage the washer l2 and compress the spring" 40 and store potential energy therein tending to move the slide 2B downward. As the downward movement of the sleeve ll continues, the shoulder it on the arm II will engage the outer end oi the trigger N and release the latter from its engagement with the shoulder 52 at about the time the top oi the disc 8'4 reaches the position of the dot anddash line B, thereby permitting the potential energy stored in the spring ll to act'to move the slide 2! downwardly and move the valve member l1 from its open position as shown in Fig. 2 to its closed position as shown in Fig. 1. when the valve member ll engages the valve seat II the kinetic energy developed bythe slide 25 will be absorbed by the spring I and the latter will be compressed an amount suflicient to permit the spring 60 to move the trigger it into engagement with the shoulder Ii thus preventing upward movement of the slide 25. The spring 50 will then be held under compression and will exert a downward pressure upon the valve member ll tending to hold the latter tightly against its seat ll. Preferably, the characteristics of the spring 50 and its arrangement are such that the force exerted thereby tending to hold the valve member I! seated is greater than the maximum force developed by the spring 40.

It will be understood that the springs 80 and 85 may be independently adjusted by adjustment of the nut ti and adjusting screw 83 respectively, so that predetermined desired pressures may be exerted upon the disc 34 when it reaches the positions indicated by the dot and dash lines A and B in Figs. 1 and 2, thus controlling the pressures at which the valve member I! will be moved from its closed position to its open position and from its open position to its closed position. Likewise, it will be understood that the potential energy developed by the spring 40 may be varied by the substitution of a spring having different characteristics thereby controlling as desired the force exerted by the spring Ill tending to move the valve member I! toward and away from its seat One important advantage oi. the construction of the invention is that substantially the entire valve operating mechanism is carried by the sleeve l3 and, consequently, the mechanism may be tested for proper seating of the valve before assembly in the casing by inserting the plug 29 in the sleeve 21 with a disc, corresponding to the disc member movably carried by said sleeve to open and close said outlet, and valve operating mechanism carried by said sleeve comprising an actuator movable in opposite directions, means providing a seat for said valve member, a movable slide, a spring connected to said slide adapted to be actuated by movement of said actuator in both directions to store potential energy therein tending to move said slide, and means for holding said slide against movement until said actuator reaches a predetermined point in its movement in one direction and until said actuator reaches a predetermined position during its movement in the opposite direction, and means for releasing said holding means when said actuator reaches a predetermined point in its movement in one of said directions and when said actuator reaches a predetermined point in the opposite direction.

2. In a pressure operated mechanism, a casing having a fluid inlet and outlet, a sleeve detachably supported within said casing having a passage communicating with said outlet, 'a valve member tion during its movement in the opposite direction, means for releasing said holding means when said actuator reaches a predetermined point in its movement in one of said directions and when said actuator reaches a predetermined point in the opposite direction, and a lost motion connection between said slide and member including a spring interposed therebetween adapted to absorb kinetic energy developed by said slide and to exert pressure upon said member tending 10 to hold it in one of its said positions.

WILBERT M. GILMAN. 

